Do you know where and when you last bought horse feed? Could you find the tag with the manufacturer’s lot number if you needed it? Horse owners in California and Arizona are scrambling to do just that, as a feed manufacturer has just issued a rare recall for a horse feed product.

Last week horse owners on the east coast were warned after six horses died from blister beetle poisoning. The toxin was sourced to their hay, which had been trucked to North Carolina from a midwestern state.

Thanks to the Internet, it is possible to get these announcements out quickly and warn people. But also thanks to the Internet, horse owners read more warnings and alerts than ever before. It can be worrisome, but look on the positive side: this news is being issued within 24 hours of the warning being made public.

But first, if you lived in the Fresno, California area, you would have seen this report–or a similar one–on your evening local news:

Here are the facts, extracted from a notice provided by the US Food and Drug Administration (FDA) on Friday:

Western Milling of Goshen, California announced on Friday that it has voluntarily recalled 50-pound bags of its Western Blend horse feed, lot 5251, manufactured on September 8, 2015.

This voluntary recall was initiated by Western Milling after it learned that an ingredient in the feed in question may contain monensin, an ionophore used in poultry and some livestock feeds that is toxic to horses.

According to the FDA, clinical signs of ionophore poisoning in horses vary depending on the dosage ingested, but can include poor appetite and feed refusal of the grain product, diarrhea, weakness, rapid heart rate, labored breathing, decreased exercise tolerance, depression, wobbly gait, colic, sweating, recumbency, and sudden death. 

The first clinical signs are often noted from 12 to 72 hours after ingesting a toxic dose and the clinical signs may linger up to about eight days. Permanent cardiac damage is possible in horses that recover after showing adverse effects.

The feed subject to this recall was distributed in September 2015 to stores in California and Arizona. All stores where the bags were sold have been notified. Of the 1,100 bags being recalled, all but 67 bags have already been reclaimed by the company.

Consumers are urged to examine any bags of Western Blend horse feed purchased in September 2015 to check and see if they have Lot 5251. Any bags with this lot number may be returned to the stores where they were purchased to receive a full refund.

The voluntary recall comes after notification that several horses who were reported to have consumed the feed being recalled while at the same equine facility have died.